Cleansing device for rock drills



Oct. 21, 1952 w. A.'MORRISON 2,614,535

CLEANSING DEVICE FOR ROCK DRILLS Filed Oct. 4, 1947 I'll INVENTOR WILLIAM A. MORRSON BY HIS ATTORNEY Patented Oct. 21, 1952 UNITED: STATES PATENT OFFICE" William A. Morrison, Easton,-Pa., assignor to In-' gersoll-Rand Company, New York, N. 'Y.-, a corporation of New Jersey I Application October-:4, 1947, Serial No. 778,013

6 This invention relates to rockdrill's'jand'more particularly to a cleansingd'evice ior fluid actuated rock drills of the reciprocatory piston type; one 0103' ectuof the invention is to minimize the amount of pressure-fluid required for actuating the rock'drill and cleansing the-hole being drilled. v 1

Another'object is'to 'utilizeallthe pressure fluid exhauste'd' 'fromthe cylinder of the rock drill for ejecting the cuttings from the holeheing drilled; 'Other'objects are to' obviate the-objectionable noises usuallyoccasioned by theexhaust fluid discharging directly" from the" rock" drill" to the at- I'n'ospherei'a-nd the spraying ofsuch oil into the atmosphere a's may be entrained in the exhaust -Anotheri-object is to permit a prolonged and uninterrupted flow-of pressure-fluid" under full lineipressurethrough the rock drillahdthe -working implement 1 for blowing the cuttings 'irom the drill 'hole and t-hold' the distributing.valveand the piston immovable duringth'e bloWing -pefiodi Other objects will-*lo'e in; part olivious and in part pointed out hereinafter. I

"ln the drawings accompanying this specification and-in which .-'sin'1ilar reference numerals v referto' similar parts; i

Figure 1 :is aside elevation, partly-broken away, of a rock drill embodying the inver'itionyand l iFig-ure- 2 isan elevation, partly-insectionfshowing amenlargedyiewof the rearwardportion of. the-"rockdrilh I Referring more particularly--" to the drawings; 20 designates, iii-general; the" rock 'drilland 2i its'-cylinder having a piston-chamber and'a piston "23 reciprocable'therein. At'the'front end of the c'ylinder "is 'a' front head 24 having a-skirt portion 25 to serve as a' closurefor the endf'of the piston chamber 22; andat-the rearwar'dendof the cylinder 2| is an enlarged bore-"26 containing a in a well'kno'wn manner to cause' 'a partial rotary movement of the piston during its rearward 7 stroke and to release theriflebar from the-ratchet ring during the workingstroke' of the "piston.

The closure? 1 'is'reta'ined in as'sembled position by a sleeve 3'! extending into'the' outer portion of the cavity 31 and containing a block 38 that seats against the ratchet ring 28 "and-overlies the head :29 to serve'as an'abutmenttherefor; The sleeve .31' and the block 38 arepressedagainst the closure a'nd the ratchet ring by 'alspring 39 seating at one end against the sieeve andat :its other end against aiplatelfl mounted'on'the-side rods 4| that secure the-front head 24I-to the cylinder"2l.u v f I The piston 23 is of the differential type'having a forward reduced pressure-surface 42- and" a relatively large. rear pressure surface 43.v 'I'he frontpre'ssure surface is constantly exposed to pressure fluid conveyed thereto by an inlet passage 44 leadingifrom a=valve chamber45,-zand I pressure fluid is intermittentlyadmittediinto the rearward'endio'f the pistonchamber-H through an inlet port 46 controlled by avalve 41*"reciprocable in the valve. chamber 45.- The valve chamberis defined by a bushingAB andits front end is inconsta'nt communication-with the inlet passage 44. I

Pressurefluid passes-tothe passage 44 through a passage" 49 --extending throughout the length of the-valve :4"! and radialports-EO in theinter mediate portion of the -valve-which open into an annular groove 5i that is iniconsta'nt communication witha supply conduita52 threadedlyconnected to=the-casing 2!. The annular'groov'e 5| is 'so located that in the foremost limiting position'of the valve41 it will be in communication with the inlet passage 46 for charging therear closure z l for -the' adjacent end of the'piston ohamher; I I

The 'cl'osur'e 21 is=suitablyrecssed to accom modateirotation mechanism; forthe pistonf2'3, comprising a ratchet ring 28 that lieswithin the closure and may be secured fixedly thereto in any suitableeinanner, and within' the-ratchet ring is the'ehead (29151 a rifle bar 3ll'that extends "axially ot the-piston chamb'erand into an elongated cavity 3I Jin'the piston 23.x The head Z fcarries the'lusual spring-pressed pawls 32 for; engage-'- ment' with the't'eeth 33 of'the ratchet ring, and theiflutes 34 on the rifle "bar are slidably -interlocked 'withrib's 35 within a nut- 36 thread'ed into thezrearwardrendof ithe pistoni23.-. The rotation endof the piston'chamber 22 and will be blankedoff bythe wall-of the valve chamber to cut-off the flow'iof pressure fluid to' theinlet passage in the otherlimitingposition of the valve.

Thefront and rear ends of the valve are constantly subj ected to pressure fluid and'constitu'te.

respectively, actuatingsurfaces '53 and 54. The

actuatingsurface 53 is of somewhat larger area than the actuating surface 54 so that, mother absence of other forces acting against th'e'valve for altering its position, the valve will"nor1nallybe actuated rearwardly and held thus by the pressure fluid acting againstthe surface 53. In order, therefore, to throw the valve-forwardly for 'ch'ar'g ing the rearward "end oithe piston chamber, said .with an additionalactuating" valve isprovided the kicker passage and through an annular groove 58 in the piston and an atmospheric exhaust port 59 in the wall of the cylinder 2|.

In order to economize in the amount of pres sure fluid required for operating the rock dllll' and fOr cleansing the drill hole, all of the pressure fluid servin to drive thepiston 23 on its working stroke is discharged into the drill hole.

channel 63 within" a drilling implement 64 se- 5 cured to the front end of the stem 6| by a clamp 65. The drilling implement 64 is shown as'con sisting of a tubular member 66 having threadedly attached'theretoa drill bit 6'! having a passage 68 which communicateswith the channelv 63 and directs the exhaust fluid toward the bottom of the drill hole 69. .1 .1 The flow. of exhaust'fluid through the piston and the drilling implement is. controlled by a valve 70 supported, in the present instance, by the rifle bar 30; "The valve 70 is preferably in the form of a sleeve which may be split, if desired, and'encircles' an end of a stem H abutting the lower end of the rifle-bar 3D. The stem H is clamped against the rifle bar by a bolt 12 which extends throughthe two and has a head 13 overlying the end of the valve to retainit on the stem H. The valve 10 is of slightly smaller diameter than the passage 62 so that it may enter readily thereinto to cooperate with the surface of the passage for controlling the flow offluid therethrough accordingly as the piston reciprocates "and is so positioned that when the'piston approaches the-end" of its working stroke the passage 62 will move out of the transverse plane of the valve to place it in. communication with the rearward end of the piston chamber shortly before'the piston reaches the end of its working stroke. To the end that an uninterrupted flow of pressure'fluid may be introducedinto the drill hole directly, from' supply. whenever the intermittent chargesof exhaustqfluid thereinto are found to be insuflicient to prevent the accumulation of cuttings around'the drill bit, the rock drill is provided with means for holding the valve 4'! selectively stationary in its foremost limiting position to place and maintain the rearward end of thepiston chamber 22 in communication with the supply conduit-52. .The means servin this function comprises a plunger 14 slidable withina chamber 75 in a head 76 forming a closure for the rearward end of the valve chamber 45. 1

j Ilhe chamber 15 has a reduced portion 11 which accommodates both the plunger and a stem portion is of the valve and has a rearward enlarged portion 78 that accommodates a head 19 of the plunger having a rearward pressure surface 80 which is subjected selectively to pressure fluid to press the plunger against the valve and hold the valve in position to communicate the rearward end of the piston chamber with the supply conduit 52-. Theend' of the plunger confronting the valve use constitutes a pressure surface 8| which is subjected to the pressure fluid within the passage 49 for normally holding the plunger out of engagement with the valve.

A closure is provided for the chamber 15 in the form of a plate 82 which, together with the head I6, is clamped to the rock drill .by bolts 83. The pressure fluid employed for pressing the plunger against-the valve is conveyed to the enlarged portion 18 of the chamber 15 by a conduit 84 having This has the added advantages of muffiing thea manually operable valve 85 that also serves to exhaust the pressure fluid from the chamber 15 to the atmosphere, v

Thegoperation ofthe device is as-follows: With the piston, 23 andthe valve 4! intheforemost limitingpositions, asv shownin Figurez of. the drawings, pressure fluidentering the passage 49 from-the supply conduit 52 and acting against the actuating surface 53 will move the valve rear;- wardl-y and cut-off the flowof pressure fluid into the rearward end of the piston chamber;,-; At the same time pressure fluid, will leakzfrom the passage 44 to the front end of the piston chamber through the natural clearance-existing between the peripheral-surface of the piston and the wall of the piston 3 amber. ar 1d,v acting against the actuating surface 42-, will liftthe piston.- :Asthe piston proceeds upwardly it next uncovers the kicker passage 56 and pressure fluidwill flow n o va e-cha be a i the ac uati g surface ,55 and again shift thevalve 4-1 forwardly. l?ressure fluid will then flow through the inlet passage 46 into the rearward end of the piston chamber and drivev the piston-.23 forwardly on its working stroke. When,'du ring this. movement of the piston, the portion'thereof defining the passage 62 moves out of engagement with the valve 10, the fluid will escape from the rear end of the piston chamber through the piston and the drilling implement 'into the drill hole and blow the cuttings therefrom.-

Shortly prior to the time the piston moves out of engagement with the valve 'l-fl ituncovers the branch passage 57. The pressure fluid acting against the surface 55 ofthe valve 41 will-then escape through-the annular. groove 58 -and the port 59 to the atmosphere and that acting against the surface 53 will lift the valve to cut-off the admission of pressure fluid into the rearend of the piston chamber and-thereby prevent-gtheflow of fluid fromsupply to the drill hole withou-tfirst serving toactuate the piston. v v

. In the event that the intermittent introduction of exhaust fluid into the drill hole is found to be. insufficient to maintain it free of cuttings, as'is sometimes the casewhen-dril1ing in softfro k; the valve85 is manipulated to cut-off communi-v cation between-the enlarged portion-18 of the chamber 15 to the-atmosphere and to-introduce pressure fluid into said chamber. Such pressure fluid acting against the actuating surface will press the plunger against the surface 54- and thereby maintain the valve.4'l in its; lowermost limiting position. Pressure fluid will then flow, as an uninterrupted stream, directly from supply through the rearward end of the piston chamber 3315 hrou h t e ri iq ndthe. drillineim' plenieii to theidrillhol freed of rock cuttingsthe valve 85 is restoredf to its former-position torelease the valve.

As wilfbe readily appreciated from the fore- 7 going description, by, exhaustingthe'fluid serving to actuate the piston from only one end of the piston chamber and "utilizing suchfluidfor cleansing the drill hole the pressure fluid're quired for bothiunctionsimayi beheldto a minimum, the oil entrained in thepressure fluid for inlet passage leading from the valve chamber to the other end of the piston chamber, a valve in the valve chamber controlled by the piston for intermittently valving pressure fluid through the last mentioned passage into the said other end of the piston chamber for actuating the pistonin the opposite direction, a drilling implement actuated by the piston, there being passages in the piston-and the drilling implement in communication with the atmosphere and constituting the sole outlet for the fluid exhausted from said other end of the piston chamber, and valve means intermittently engaging the piston for controlling the flow ofexhaust fluid through the last mentioned passages. I

2. In a fluid actuated rock drill, the combination of a casing having a piston chamber, a piston reciprocable in the piston chamber, a passage in the casing for constantly conveying pressure fluid from a source of supply to the front end of the piston chamber for actuating the piston rearwardly, a valve chamber in the casing, an inlet passage leading from the valve chamber to the other end of the piston chamber, a valve in the valve chamber controlled by the piston for intermittently valving pressure fluid through the second mentioned passage into the rear end of,

the piston chamber for actuating the piston forwardly, a drilling implement actuated by the piston, said piston and drilling implement having passages in communication with the atmosphere and the rear end of the piston chamber and constituting the sole outlet for the fluid exhausted from the rear end of the piston chamber, and a valve within the piston to cooperate intermittently with the piston for controlling the flow of exhaust fluid through the passages in the piston and the drilling implement.

3. In a fluid actuated rock drill, the combination of a casing having a piston chamber, a piston reciprocable in the piston chamber, a passage in the casing for constantly conveying pressure fluid from a source of supply to the front .end of the piston chamber for actuating the piston rearwardly, a valve chamber in the casing, an inlet passage leading from the Valve chamber to the other end of the piston chamber, a valve.

in the valve chamber controlled by the piston for saw effect a thorou h o a c sineii av ne aiipi ton'ch benga m e ton recipro'cableinthe; pifston' chamber; arpassage in the casing ,ior constantly conveying" pressure ait-sea piston, said piston and-drillingimplement hating) passages incommunication with meatmcs== phere and the rear endof the--piston-.chamber-' and constituting; the 1 sole *outlet for the fluid exi haustedi from the rear end of the piston" chain ber-,avalve "in the rock'drill to intermittentlyextend intothe passage in the pistonac'coi dinglyi as" the" piston reciprocates within the pi'st on chamber for controlling the fiOW'Of exhaust fluidthrough the piston, and means for securing the last mentioned'valve to the roclsdri-ll Y j 4. In a fluid jactuated rock drill," thezcombin' "e fluid from a'source of supply to the front'end'of the piston chamber for actuating the piston rearwardly, a valve chamber in the casing, an inlet passage leading from the valve chamber to the other end of the piston chamber, a valve in the valve chamber controlled by the piston for intermittently valving pressure fluid only to the rearward end of the piston chamber for actuating the piston forwardly, a drilling implement actuated by the piston, said piston and drilling implement having passages in communication with the atmosphere and the rear end of the piston chamber intermittently valving pressure fluid through the I second mentioned passage into. the rear end of the piston chamber for actuating the piston forwardly, a drilling implement actuated by the and constituting the sole outlet for the fluid exhausted from the rear end of the piston chamber, a rifle bar having spiral flutes interlocking slidably with the piston for causing rotary movement of the piston, and a valve on the rifle bar to intermittently cooperate with the surface which defines the passage in the piston accordingly as said piston reciprocates within the piston chamber for controlling the flow of exhaust fluid through the piston.

5. In a fluid actuated rock drill, the combina tion of a casing having a piston chamber, a piston reciprocable in the piston chamber, a passage in the casing for constantly conveying pressure fluid from a source of supply to the front end of the piston chamber for actuating the piston rearwardly, a valve chamber in the casing, an inlet passage leading from the valve chamber to the other end of the piston chamber, a valve in the valve chamber controlled by the piston for valving pressure fluid intermittently into only the rearward end of the piston chamber, a drilling implement actuated by the piston, said piston and drilling implement havingrpassages in communication with the atmosphere and the rear end of the piston chamber and constituting the sole outlet for the fluid exhausted from the rear end of the piston chamber, a stationary valve in the rock drill cooperating with the piston to alternately open and close the passage in the piston accordingly as the piston moves away from and toward said stationary valve for controlling the flow of exhaust fluid through the last mentioned passages, and means for selectively holding the first mentioned valve immovable in the valve chamber to permit an uninterrupted flow of pressure fluid from the valve chamber through the rear end of the piston chamber and the last mentioned passages into the hole being drilled.

6. In a fluid actuated rock drill, the combinati-onof a casing having a piston chamber, a piston reciprocable in the piston chamber, a passage for constantly conveying pressure fluid from a source of supply to the front end of the piston chamber for actuating the piston rearwardly, a valve chamber in the casing, an inlet passage leading from the valve chamber to the other end of the piston chamber, a valve in the valve chamber controlled by the piston for valving pressure fluid intermittently into only the rearward end of the piston chamber, a drilling implement actuated by the piston, said piston and drilling implement having passages in communication with the atmosphere. and the rear end of the piston chamber and, constituting the sole outlet for the fluid exhausted from the rear end of the piston chamber,. a, stationary valve in the rock drill cooperating with the piston to alternately open and close the passage in the, piston accordingly as the piston reciprocates within the piston chamber for controllingthe flow of exhaust fluid through the last mentioned passages, a fluid actuated plunger for holding'the'first mentioned valve immovable to permit an uninterrupted flow of pressure fluid from the valve chamber through the rear end of the piston chamber and the last mentioned passages into a hole being drilled, and means for selectively controlling theflow of pressure fluid to the plungen.

. WILLIAM A. MORRISON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Morrison Aug. 10, 1943 

